[flutter_tool] More gracefully handle Android sdkmanager failure (#37194)

packages/flutter_tools/lib/src/android/android_workflow.dart

@@ -258,6 +258,7 @@ class AndroidLicenseValidator extends DoctorValidator {
       return LicensesAccepted.unknown;
     }
 
+    try {
       final Process process = await runCommand(
         <String>[androidSdk.sdkManagerPath, '--licenses'],
         environment: androidSdk.sdkManagerEnv,
@@ -277,6 +278,10 @@ class AndroidLicenseValidator extends DoctorValidator {
         .asFuture<void>(null);
       await Future.wait<void>(<Future<void>>[output, errors]);
       return status ?? LicensesAccepted.unknown;
+    } on ProcessException catch (e) {
+      printTrace('Failed to run Android sdk manager: $e');
+      return LicensesAccepted.unknown;
+    }
   }
 
   /// Run the Android SDK manager tool in order to accept SDK licenses.
@@ -296,6 +301,7 @@ class AndroidLicenseValidator extends DoctorValidator {
       throwToolExit(userMessages.androidSdkManagerOutdated(androidSdk.sdkManagerPath));
     }
 
+    try {
       final Process process = await runCommand(
         <String>[androidSdk.sdkManagerPath, '--licenses'],
         environment: androidSdk.sdkManagerEnv,
@@ -313,6 +319,11 @@ class AndroidLicenseValidator extends DoctorValidator {
 
       final int exitCode = await process.exitCode;
       return exitCode == 0;
+    } on ProcessException catch (e) {
+      throwToolExit(userMessages.androidCannotRunSdkManager(
+          androidSdk.sdkManagerPath, e.toString()));
+      return false;
+    }
   }
 
   static bool _canRunSdkManager() {

packages/flutter_tools/lib/src/base/user_messages.dart

@@ -102,6 +102,10 @@ class UserMessages {
       'Android sdkmanager tool not found ($sdkManagerPath).\n'
       'Try re-installing or updating your Android SDK,\n'
       'visit https://flutter.dev/setup/#android-setup for detailed instructions.';
+  String androidCannotRunSdkManager(String sdkManagerPath, String error) =>
+      'Android sdkmanager tool was found, but failed to run ($sdkManagerPath): "$error".\n'
+      'Try re-installing or updating your Android SDK,\n'
+      'visit https://flutter.dev/setup/#android-setup for detailed instructions.';
   String androidSdkBuildToolsOutdated(String managerPath, int sdkMinVersion, String buildToolsMinVersion) =>
       'Flutter requires Android SDK $sdkMinVersion and the Android BuildTools $buildToolsMinVersion\n'
       'To update using sdkmanager, run:\n'

packages/flutter_tools/test/general.shard/android/android_workflow_test.dart

@@ -42,8 +42,22 @@ void main() {
     return (List<String> command) => MockProcess(stdout: stdoutStream);
   }
 
+  testUsingContext('licensesAccepted returns LicensesAccepted.unknown if cannot find sdkmanager', () async {
+    processManager.canRunSucceeds = false;
+    when(sdk.sdkManagerPath).thenReturn('/foo/bar/sdkmanager');
+    final AndroidLicenseValidator licenseValidator = AndroidLicenseValidator();
+    final LicensesAccepted licenseStatus = await licenseValidator.licensesAccepted;
+    expect(licenseStatus, LicensesAccepted.unknown);
+  }, overrides: <Type, Generator>{
+    AndroidSdk: () => sdk,
+    FileSystem: () => fs,
+    Platform: () => FakePlatform()..environment = <String, String>{'HOME': '/home/me'},
+    ProcessManager: () => processManager,
+    Stdio: () => stdio,
+  });
+
   testUsingContext('licensesAccepted returns LicensesAccepted.unknown if cannot run sdkmanager', () async {
-    processManager.succeed = false;
+    processManager.runSucceeds = false;
     when(sdk.sdkManagerPath).thenReturn('/foo/bar/sdkmanager');
     final AndroidLicenseValidator licenseValidator = AndroidLicenseValidator();
     final LicensesAccepted licenseStatus = await licenseValidator.licensesAccepted;
@@ -168,7 +182,20 @@ void main() {
 
   testUsingContext('runLicenseManager errors when sdkmanager is not found', () async {
     when(sdk.sdkManagerPath).thenReturn('/foo/bar/sdkmanager');
-    processManager.succeed = false;
+    processManager.canRunSucceeds = false;
+
+    expect(AndroidLicenseValidator.runLicenseManager(), throwsToolExit());
+  }, overrides: <Type, Generator>{
+    AndroidSdk: () => sdk,
+    FileSystem: () => fs,
+    Platform: () => FakePlatform()..environment = <String, String>{'HOME': '/home/me'},
+    ProcessManager: () => processManager,
+    Stdio: () => stdio,
+  });
+
+  testUsingContext('runLicenseManager errors when sdkmanager fails to run', () async {
+    when(sdk.sdkManagerPath).thenReturn('/foo/bar/sdkmanager');
+    processManager.runSucceeds = false;
 
     expect(AndroidLicenseValidator.runLicenseManager(), throwsToolExit());
   }, overrides: <Type, Generator>{

packages/flutter_tools/test/src/mocks.dart

@@ -152,11 +152,12 @@ typedef ProcessFactory = Process Function(List<String> command);
 /// A ProcessManager that starts Processes by delegating to a ProcessFactory.
 class MockProcessManager implements ProcessManager {
   ProcessFactory processFactory = (List<String> commands) => MockProcess();
-  bool succeed = true;
+  bool canRunSucceeds = true;
+  bool runSucceeds = true;
   List<String> commands;
 
   @override
-  bool canRun(dynamic command, { String workingDirectory }) => succeed;
+  bool canRun(dynamic command, { String workingDirectory }) => canRunSucceeds;
 
   @override
   Future<Process> start(
@@ -167,7 +168,7 @@ class MockProcessManager implements ProcessManager {
     bool runInShell = false,
     ProcessStartMode mode = ProcessStartMode.normal,
   }) {
-    if (!succeed) {
+    if (!runSucceeds) {
       final String executable = command[0];
       final List<String> arguments = command.length > 1 ? command.sublist(1) : <String>[];
       throw ProcessException(executable, arguments);